How does the Next Permutation algorithm work?
An algorithmic question about generating the next lexicographical arrangement of numbers.
Why Interviewers Ask This
This tests your ability to manipulate arrays logically and handle edge cases in permutation generation.
How to Answer This Question
Explain the three steps: find the pivot, swap with the next larger element, reverse the suffix. Use an example like [1,2,3] -> [1,3,2].
Key Points to Cover
- Pivot identification
- Swap logic
- Suffix reversal
- Edge case handling
Sample Answer
The Next Permutation algorithm rearranges numbers into the next lexicographically greater order. First, find the pivot index where nums[i] < nums[i+1]. Then, find the smallest element to the right of the pivot that is la…
Common Mistakes to Avoid
- Incorrect pivot finding
- Wrong swap element
- Forgetting to reverse suffix
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